1. Field of the Invention
The present invention relates to an audio signal recording/reproducing apparatus and, more particularly, to an apparatus capable of automatically adjusting a variation caused in the signal phase due to any signal process executed by an external digital device in a digital audio system.
2. Description of the Related Art
In an audio signal recording/reproducing apparatus which records an audio signal on a recording medium and reproduces the same signal from the recording medium, there may occur an undesired phenomenon that, when overwriting or the like is executed on the recorded audio signal by an external digital device during an editing operation based on a reference time code, the phase of the recorded audio signal is delayed in comparison with the reference time code.
Such phase delay is dependent on the amount of the delay derived from the process executed by the external digital device. And in case a plurality of external digital devices are connected, it follows that the delays in the individual devices are accumulated.
For the purpose of compensating such phase delay, it has been generally customary in the prior art that the audio signal recording/reproducing apparatus is equipped with an advance reproducing function for outputting the reproduced signal with a sufficient margin lead of the phase with respect to the reference time code, and also a delay adjusting function for delaying the advanced output to thereby attain a coincidence with the phase of the reference time code.
If a user checks the delay in each device by utilizing such delay adjusting function and manually adjusts the phase in conformity with the result of such check, it becomes possible to edit, record and reproduce the audio signal at any given position indicated on the recording medium by the reference time code while disregarding harmful influence that may be caused by the delay in the external digital device.
In such phase adjustment, however, the amount of the signal delay in each external digital device needs to be detected prior to the adjustment which consequently complicates the operation. And in case a plurality of external devices are connected, calculation of the accumulated delays is necessary, and the procedure thereof also renders the adjustment intricate to eventually induce errors.